A cutting tool for metalworking operations may comprise a cutting insert removably attached to an insert holder. The cutting insert may be provided with a plurality of cutting portions, each having at least one cutting edge. Generally speaking, only one of the cutting portions is operative (or, “active”) at any given time while the remaining portions are regarded as “inoperative” or “non-active”.
Examples of such cutting tools are disclosed in, for example, US 2011/0255926, U.S. Pat. No. 6,612,207, U.S. Pat. No. 6,942,434 and U.S. Pat. No. 7,682,109.
During said metalworking operations a cutting force is applied on the cutting insert at the cutting edge. The direction of the cutting force is substantially downwards and somewhat inwards towards the central body. The said cutting force generates a torque about a pivot point, the pivot point typically being a forwardmost abutment point between a lower surface of the cutting insert and a lower supporting surface of the insert holder. The torque forces the cutting insert to rotate in a rotational direction about the pivot point thereby urging the lower abutment surface on the cutting insert away from the lower supporting surface on the insert holder. To prevent the rotational displacement of the cutting insert, the insert holder has an abutment surface that faces against the rotational direction.